Since there are many things to discover in the game, it's best that these things are recorded somewhere you can come back to any time. That's where the Collection Book comes in! This is where all the Dragons, plants, and buildings you've discovered so far in the game are found. When there's a new entry, a book icon will appear at the upper left corner. Tapping it will direct you to the Collection Book. You can always check it out any time you like by tapping on the book statue near the Pet Dragon House in your Home Island.

In the Collection Book, you can see the things you've discovered in the game, as well as those that you have yet to explore. When you have discovered something new, you will see a lock icon on it and it's ready to be unlocked. Tap the lock to see the description of each entry. The date displayed at the bottom shows the date you unlocked the entry.